The only reason why Apple does not include an internal SD card reader is because that would simply cut into the profit margins. They wouldn't be able to up trade you to go with a higher capacity model, and they also wouldn't be able to sell you an external SD card reader (yes, apple makes sd card adaptors.)

It's amusing to watch someone who claims to have experience with electronics design claim that the only reason to leave out a SD slot is greed.

Tell us, electronics designer, how much space does a SD card reader take up in a phone chassis?